Solid-phase

Solid-phase assays include the so-called "dipstick" or "dipstick comb" tests that date back to the early 1980s.

The tests are comprised of solid, nonporous supports onto which analyte capture molecules are immobilized. Some assays simply require the user to dip the test into a specimen and then wait for a color change indicating the test result. To perform most assays of this type, the dipsticks are incubated with patient specimens followed by an initial wash step, addition of signal reagent, and a final wash step. (See "How it works" for more information on how these tests are performed and how they work.) Most tests can be completed in one hour or less.